On Thu, May 23, 2024 at 10:40:07PM -0700, Nicolin Chen wrote: > On Thu, May 23, 2024 at 06:42:56AM +0000, Tian, Kevin wrote: > > > From: Nicolin Chen <nicolinc@xxxxxxxxxx> > > > Sent: Saturday, April 13, 2024 11:47 AM > > > > > > Introduce a new ioctl to set a per-viommu device virtual id that should be > > > linked to the physical device id (or just a struct device pointer). > > > > > > Since a viommu (user space IOMMU instance) can have multiple devices > > > > this is true... > > > > > while > > > it's not ideal to confine a device to one single user space IOMMU instance > > > either, these two shouldn't just do a 1:1 mapping. Add two xarrays in > > > > ...but why would one device link to multiple viommu instances? > > That's a suggestion from Jason, IIRC, to avoid limiting a device > to a single viommu, though I can't find out the source at this > moment. > > Jason, would you mind shed some light here? We could probably do it either way, it just doesn't seem like there is a strong reason to limit a device to a single viommu even if in practice that is how everyone will use it. Jason
